In the World Wide Web, a very large number of resources is made available through digital libraries. The existence of many individual digital libraries, maintained by different organizations, brings challenges to the discoverability, sharing and reuse of the resources. A widely-used approach is metadata aggregation, where centralized efforts like Europeana facilitate the discoverability and use of the resources by collecting their associated metadata. The cultural heritage domain embraced the aggregation approach while, at the same time, the technological landscape kept evolving. Nowadays, cultural heritage institutions are increasingly applying technologies designed for the wider interoperability on the Web. In this context, we have identified the Schema.org vocabulary as a potential technology for innovating metadata aggregation. We conducted two case studies that analysed Schema.org metadata from collections from cultural heritage institutions. We used the requirements of the Europeana Network as evaluation criteria. These include the recommendations of the Europeana Data Model, which is a collaborative effort from all the domains represented in Europeana: libraries, museums, archives, and galleries. We concluded that Schema.org poses no obstacle that cannot be overcome to allow data providers to deliver metadata in full compliance with Europeana requirements and with the desired semantic quality. However, Schema.org’s cross-domain applicability raises the need for accompanying its adoption by recommendations and/or specifications regarding how data providers should create their Schema.org metadata, so that they can meet the specific requirements of Europeana or other cultural aggregation networks.